The present invention generally relates to balls and more specifically to a skeleton ball that may be readily adapted for exercise or rehabilitation in or around water.
Balls used for recreation, physical training and physical rehabilitation are widely known in the literature. Such balls may be constructed as inflated membranes, rigid shells or skeletal space frames. The former two constructions are beyond the scope of the present invention.
Skeleton balls have the unique property of being easily grasped by passing the fingers of the hand through openings and gripping the skeletal elements. This property is especially desirable for physical education of handicapped, disabled, injured or young individuals with limited manual dexterity or poor hand-eye coordination. Skeleton balls analagously lend themselves to games whereby the ball is projected towards a peg or hook in a fashion similar to conventional ring-toss games.
Balls used in and around water, such as at the beach or in a swimming pool, must float to facilitate use and avoid loss. Skeleton balls generally float poorly or not at all unless some means of inflation of the skeletal elements is provided. A skeleton ball that may be readily designed to have inherent bouyancy without need for inflation would be an improvement over previously known skeleton balls.
Skeleton balls are especially valuable as hydrotherapy aids. Hydrotherapy consists of performing motion exercises while partially immersed in a swimming pool or tank specifically designed for such purposes. Skeleton balls, being easily grasped and providing substantial fluid resistance, are used to increase muscle activity and metabolic output. There are available rather complex appliances that may be affixed to the limbs with straps or similar means; they also serve to increase fluid resistance. It would be desirable to adapt the simplicity of the skeleton ball to meet the needs served by complex strap-on appliances.
Storage and transport of balls has, in the past, been hindered by the relatively large volume of space required per ball. Institutions with large inventories, and physical trainers who travel with equipment to various training sites would benefit greatly from a means to reduce the storage space requirements of their balls. Inflated balls may be collapsed by deflating them; the extreme inconvenience of the deflation-inflation cycle negates this as a viable means of reducing short-term storage requirements. A soft, pliable skeleton ball may be readily crushed to reduce its volume, however, ease of crushing is generally antagonistic to playability.
Balls suitable as tote bags or containers for towels or other objects are widely known, most of them being constructed as rigid shells. Skeleton balls suitable as totes or containers are less well known, but do exist. In the past, adapting a skeleton ball to a tote bag generally involved the use of discrete snap-type joints that allowed a region of the ball's surface grid to be opened. Such joints are not only expensive to fabricate, they are vulnerable to wear and breakage. A skeleton ball suitable for use as a tote, but not requiring any separate joints or snaps would be a definite improvement over previously known skeleton balls.
Heretofore, skeleton balls have been constructed as assemblies of large numbers of discrete, elongated elements and as integrally molded frames. Skeletons comprising large numbers of discrete elements are costly to produce due to the large number of joints required, generally at least two per element. In addition, specialized material preparation is often required prior to the joining operations. Molding integral frames requires considerable capital equipment and usually separate operations to join two or more sections. More economical fabrication methods would be desirable.
U.S. Pat. No. 3,889,950, teaches a skeleton ball comprised of a relatively large number of elongated elements with at least twice as many joints; the primary embodiment shown comprises thirty elements and sixty joints. There is no provision for collapsing the ball for storage other than crushing it flat. Flotation is achieved only through separate means for inflation of tubular elements. This ball is suitable as a tote bag only if separate means for opening and closing (i.e. snaps) is provided. Fabrication of the ball requires the elongated elements be joined at the ends and also midway along their length, the latter being cumbersome and relatively expensive.
U.S. Pat. No. 4,813,674, teaches a specialized skeleton ball comprised of elongated strip material specially prepared and assembled in a complex fashion. The ball has no provision for flotation or collapsibility and is not easily grasped due the small openings and nature of the elongated strip material. The ball is not suited for use as a tote or container. The ball is specifically intended for the game of takraw, a South East Asian game mostly foreign to the United States. Takraw is similar to American vollyball or soccer in that the ball is struck with portions of the body; the ball preferrably has a predominantly closed smooth surface with relatively few small openings.
Previously known skeleton balls, including the above mentioned balls, suffer from several deficiencies: they are not inherently bouyant or water compatible; they do not readily collapse or fold to reduce their volume; they are not suitable as totes or containers unless provided with separate means for opening and closing them; and they are relatively expensive to fabricate due to excessively large numbers of elements and joints and/or specialized material preparation or processing.
Accordingly, among the objects of the present invention are:
to provide a skeleton ball that is water compatible and inherently bouyant without need for inflation;
to provide a skeleton ball that may be easily and rapidly folded to reduce its volume;
to provide a skeleton ball that is suitable as a tote or container without need for snaps, clasps or other separate means for opening and closing it;
to provide a skeleton ball that is readily fabricated from widely available materials with a minimum of capital equipment and processing;
to provide a skeleton ball that comprises relatively few discrete elements and joints, the majority of the connections being frictionally secured; and
to provide a skeleton ball whose geometry and composition is readily adapted or modified to meet a diverse range of applications.
This listing of objects and advantages is not intended to be exhaustive or limiting, but summarily brief. Further objects and advantages will be apparent from consideration of the detailed description of the invention.